My 21 YO doesn't live at home, and hasn't since he was 19. Maybe its time for your son to have his own space.Either way, he's an adult. If you don't like his behaviour in your home, you can ask him to move out, or you can ask him to talk to you about it, but if he doesn't want to open up, it's his business. As long as he's meeting his responsibilities, he's being an adult.On a different note, what is it with all of these adult children being allowed to remain in mom & dad's house? It doesn't teach them much about being a responsible contributing member of society, IMO...

He's an adult, as long as he is going to work/school and doing everything that is expected why are you worried?You really haven't given us any information to comment on though so maybe there is more to it. If there is, please let us know everything so we can comment appropriately.